There are many different ISO standards, all of which have different values and mostly are targeting print production work. We account for that using the sRGB standard, which is 80 cd/m2 and requires virtually no ambient light. 200 cd/m2 is a level that more people are likely to use where they have ambient light as almost all the ISO standard are based on virtually no ambient light at all.Reply

This falls somewhere between graphics cards and monitors so not sure how much of your focus it can be, but -- what is a practical approach to gaming at this resolution? One approach is obviously the unlimited budget, i.e. 3x Titan or similar. You could argue that since the monitor costs that much, the cards should have a similar budget. But to my personal sensibility the cards are much more disposable than a (good) monitor should be; and thus I'd be much more willing to spend $3K on a monitor than on graphics cards. But that leaves the question of, what do you do in the meantime until the graphics cards catch up? Is there an acceptable approach using say a single 780 or dual 770 or their ATI equivalents that along with perhaps low/no AA and less extreme game settings especially where they least matter that still looks good?Reply

I hope the full review will indeed do more research into a 4K monitor as a viable power-user monitor, with photo editing, gaming and multitasking as a user's point of view. While it might be the only way to truely enjoy 4K gaming, three Titans or GTX 780's seems a little overboard as bruce2k says, a monitor seems way more justified to spend that amount of money on than a bunch of GPU's.

So in that aspect, I'd like to know from the full review if FSAA is actually needed or perceptible at 4K and how the experience is on this screen with 1920x1080 FSAA.

Also the benefit of having a 2GB card, a 3/4GB card and a 6GB card is something worth exploring in the 4K realm.

I'd like to know how other OS'es handle 4K, like MacOS X 10.8 and Mavericks Beta, even Ubuntu should get a chance.Reply

At only 140DPI you're probably still going to want some level of AA. I have a 2560x1600 screen and sit at the same distance from it as I did with my older, smaller, screens. The big one just fills more of my FoV.

On a notional 22" screen quadHD gives 200DPI; AA won't have much to offer here. An equally notional 14.7"/300 DPI laptop screen should be able to go completely AA free.Reply

"Using an NVIDIA GTX 660 Ti card, with the most recent drivers, you can enable MST mode on the ASUS to provide a full 3840x2160 signal at 60p over a single DisplayPort cable."

That statement is incorrect. It should read as "you can enable MST mode on the ASUS to provide a two 1920x2160 signals at 60p over a single DisplayPort cable which are combined into one single seamless 3840x2160 picture on the display."

This is a very important distinction. Since the display looks like two displays to the GPU, you cannot use DirectX or OpenGL software properly when using an nVidia GPU with currently available drivers. This is because nVidia Surround only works in 3x1 configurations. ASUS has stated that nVidia will be releasing an updated driver when this monitor ships (July 16) that will support 2x1 surround. So hopefully this will all be resolved soon.

Maybe nVidia will be nice and enable, 4x1, 2x2, 5x1, 6x1, 3x2 mosaic configurations on GeForce cards as well. The hardware is certainly capable but nVidia has locked down the driver preventing this. One can dream...Reply

However, the second image in your article really doesn't bode well for general display 2x1 Surround support. NVIDIA may be using some driver specific hacks for these kinds of monitors which would really be disappointing.

Is it possible for you guys to test DirectX/OpenGL support on the PQ321Q when using 2 HDMI cables rather than a single DP cable. I'm curious to see if the driver still shows it as one display or if it shows up as two displays or as a unified display.Reply

On a monitor this expensive, it's disappointing that there isn't perfect color calibration out of the box. If they get 4K monitors under $1000 then I understand compromises may need to be made, but there shouldn't be any compromises at the $3500 price point.Reply

- Could you please test responsiveness objectively; with PixPerAn's chase test for example. I believe it's a very useful and representative test for response time even by itself (without samples from other monitors to compare to).- Backlight bleeding and panel uniformity- Input lag- 1080p scaling or if you could somehow measure how well (or not) this model handles 1080p content and whether there's a benefit of running 1080p on 4K. This mostly applies for films and plugging in a console.

I realize some of those might already be planning, but I thought I'd mention them anyway. Thanks for considering.Reply

1080p scaling will likely be measured using the 1080 scaling pattern on the new Spears and Munsel Blu-ray disc. I'll compare native scaling to the Oppo players I have on hand, and the LG BP730 I have here for review as well.

Input lag I'll test as best I can, with a possible new option as well, but since the display may not support DirectX correctly at 2160p60 before I try to test, I'm not certain how accurate I can get. I'll do some PixPerAn chase images as well.Reply

While we await Chris's review, you can watch a video of ASUS PQ321Q being driven by two ASUS GTX 780 DirectCU II in 2-way SLI over single DisplayPort cable using unreleased NVIDIA Drivers where 2x Surround is working:http://www.youtube.com/watch?v=PSHrcAWS2C8Reply

Relative to most, it's pre-calibrated. Gamut volume is a different matter, which could be backlight or panel related. It's not perfect, but the number of panels that have arrived more accurate out-of-the-box than this can likely be counted on one hand.Reply

I would be very interested in hearing how this monitor would work with different computer hardware, such as different GFX solutions from AMD, Nvidia cards and Intel under different versions of Windows. Preferably also how it works with Macbooks of different kinds, both on OSX 10.8 and 10.9.Reply

That low amount of brightness steps: actually I think 31 steps are fine. Think of it.. if 100 steps are provided, how much of a difference do you actualy percieve switching just 1 step? Would it matter at any point if the display was set to 52 or 51? I think with 31 steps they're making good use of all of them.

BTW: I'd never buy a monitor without ambient light sensor again. Haven't felt the need to adjust brightness at all since I bought mine!Reply

I've never felt the need to adjust the brightness of anything except a laptop (down when I'm pushing the battery) past initial setup. I briefly had it enabled on one of my desktop monitors; but having brightness levels change every few minutes when I moved and varied the amount of shadow I was casting on the sensor was utterly obnoxious and had it disabled within an hour or two.Reply

Shouldn't this article be tagged "Displays"? That appears to be the main monitors/lcds/whatever tag that's used in the menu on the front page of the site, and since it isn't tagged, this article doesn't appear when you click on PC Components -> Displays. That's pretty bad since the new mobile layout does not show pipeline stories outside of the tag views.Reply

I'm thinking of buying a Seiki 39" 4K monitor after it gets HDMI 2.0 or displayport. I heard the panel quality is actually quite decent, but it performs poorly due to Seiki's lack of effort in tuning it before shipping them out. Is it necessary to buy a calibrating instrument? I'm just an average user that plays a bit of games and watches a lot of HD movies and UHD clips. If I borrow one from a friend and calibrate it once, how long could it last before I absolutely have to calibrate it again?Reply

How is the screen quality when the resolution is turned down to say 1920*1080, I imagine if you have a mid-range gpu gaming at native spec will not be possible. Also I suppose this also tests Window's new dpi scaling mechanism.Reply

Since NVIDIA's latest beta drivers now support 2 display Surround mode or 2 device 'mosaic' mode or 'tiled' 4K displays (call it whatever), I thought I'd ask for some data related to 3840x2160@60Hz, if time permits. Reply